scholarly journals Regional patterns in shallow water invertebrate assemblages on offshore oil and gas platforms along the Pacific continental shelf

2019 ◽  
Vol 95 (4) ◽  
pp. 617-638
Author(s):  
Henry M Page ◽  
Susan F Zaleski ◽  
Robert J Miller ◽  
Jenifer E Dugan ◽  
Donna M Schroeder ◽  
...  
Keyword(s):  
Shallow Water ◽  
Oil And Gas ◽  
Spatial Scales ◽  
Regional Patterns ◽  
Geographical Patterns ◽  
The Pacific ◽  
Local Patterns ◽  
Invertebrate Assemblages ◽  
Offshore Oil And Gas ◽  
Offshore Oil

We explored biogeographical and local patterns in the composition of shallow water (≤18 m depth) invertebrate assemblages inhabiting California offshore oil and gas platforms using multivariate analysis of diver- conducted photographic data collected from 23 platforms in 2013–2014. We evaluated the potential importance of sea surface temperature (SST) and other physical and biological factors in driving observed patterns in these assemblages. Prior to this analysis, platforms were grouped into four regions based on local differences in annual mean SST. The composition of invertebrate assemblages varied significantly among the four regions, reflecting differences in the relative abundances of certain anemone, bryozoan, sponge, and bivalve taxa. However, invertebrate assemblages varied idiosyncratically among platforms within a region. Variation in platform assemblages was associated with SST across regions; however, assemblages of platforms in the southeast Santa Barbara Channel were distinct due to the high cover of a non-native bryozoan, Watersipora subatra (Ortmann, 1890). The existence of geographical patterns in the composition of platform invertebrate assemblages and the colonization of one platform by a native bryozoan with southern affinities during elevated SST of 2014–2015 suggest that these assemblages may be useful over broad spatial scales as barometers of short- and longer-term changes in ocean climate. However, over smaller spatial scales, the idiosyncratic differences in invertebrate assemblages among platforms within regions indicates that these assemblages would have to be considered on a platform-by-platform basis under various decommissioning scenarios.

scholarly journals Oceanographic gradients and patterns in invertebrate assemblages on offshore oil platforms

2008 ◽  
Vol 65 (6) ◽  
pp. 851-861 ◽  
Author(s):  
Henry M. Page ◽  
Carolynn S. Culver ◽  
Jenifer E. Dugan ◽  
Brent Mardian
Keyword(s):  
Exotic Species ◽  
Oil And Gas ◽  
Function Analysis ◽  
Sea Anemones ◽  
Oil Platforms ◽  
Offshore Oil Platforms ◽  
Invertebrate Assemblages ◽  
Offshore Oil And Gas ◽  
Channel Patterns ◽  
Offshore Oil

Abstract Page, H. M., Culver, C. S., Dugan, J. E., and Mardian, B. 2008. Oceanographic gradients and patterns in invertebrate assemblages on offshore oil platforms. – ICES Journal of Marine Science, 65: 851–861. We explored variability in the composition and cover of subtidal macroinvertebrate assemblages, and the recruitment and growth rates of selected invertebrate species, on seven offshore oil and gas platforms arrayed across a gradient in oceanographic conditions in the Santa Barbara Channel, CA, USA. The major macroinvertebrate taxa (sea anemones, mussels, barnacles, tubiculous amphipods, hydroids, and sponges) were common to all platforms. However, discriminant function analysis (DFA) revealed that the assemblages of two platforms (Gilda and Gail) clearly differed from the other platforms, a pattern attributable, in part, to the presence of conspicuous exotic species (the anemone, Diadumene sp., and encrusting bryozoan, Watersipora subtorquata) on these platforms. If these exotic species were excluded from the analysis, platforms in proximity to each other generally tended to have invertebrate assemblages more similar to each other than to platforms located farther away. Spatial variation in barnacle recruitment onto ceramic plates and mussel growth rate reflected prevailing oceanographic gradients. The existence of along-channel patterns in the composition of platform invertebrate assemblages, and in invertebrate recruitment and growth associated with oceanographic gradients, suggests that assemblages attached to platforms or other artificial structures may be useful barometers of short and perhaps longer term change in ocean climate.

scholarly journals Fishes and invertebrates of oil and gas platforms off California: an introduction and summary

2019 ◽  
Vol 95 (4) ◽  
pp. 463-476 ◽  
Author(s):  
Milton S Love
Keyword(s):  
Southern California ◽  
Oil And Gas ◽  
Current Operator ◽  
Outer Continental Shelf ◽  
The Pacific ◽  
Introductory Paper ◽  
Removal Weight ◽  
Offshore Oil And Gas ◽  
Bottom Depth ◽  
Offshore Oil

This paper serves as an introduction to a symposium on the role that California oil and gas platforms serve as habitats for fishes and invertebrates. As of 2019, there are 27 platforms in state and federal waters off California, and the decommissioning of some of these platforms is imminent. Thus, consideration of whether to completely remove a platform or cut it off at some depth below the sea surface and retain the submerged portion as a reef is a decision that will occur in the near future. The objectives of the 10 papers in this dedicated issue of the Bulletin of Marine Science are to: (1) increase scientific understanding of the inter- and intrarelationships of fish and invertebrate populations at offshore oil and gas platforms and natural reefs within the Southern California Bight; (2) determine the extent of influence of platform assemblages on southern California and the Pacific coast populations of fishes and invertebrates; and (3) synthesize relevant reports, existing peer-reviewed literature, and new data analyses into a single peer-reviewed reference. This introductory paper contains a synopsis of all extant California platforms including information on: (1) the original operator, (2) the current operator of records, (3) the date the platform was installed, (4) the first production date, (5) the platform's distance from shore [including whether it is state or outer continental shelf (OCS) waters], (6) the bottom depth of the platform, (7) the number of well slots, (8) the number of conductors, (9) what the platform produces (oil and/or gas), (10) the platform jacket dimensions [generally at the seafloor (bottom)], (11) the platform's footprint, (12) the midwater surface area, (13) the total removal weight, (14) the platform location, (15) the shell mound size, (16) the shell mound volume, (17) the shell mound height, (18) the center of the shell mound location, and (19) the bottom slope. In addition, we present an overview of all previous research on the biology and ecology of California platform organisms.

scholarly journals WAVE HINDCASTS AND MEASUREMENTS BASS STRAIT

1980 ◽  
Vol 1 (17) ◽  
pp. 23
Author(s):  
M.N. Silbert ◽  
T.P. Barnett ◽  
O.J.H. Peters ◽  
R.C. Hamilton
Keyword(s):  
Shallow Water ◽  
Oil And Gas ◽  
Barometric Pressure ◽  
Gas Production ◽  
Offshore Wind ◽  
Electromagnetic Current ◽  
Oil And Gas Production ◽  
Wave Hindcast ◽  
Offshore Oil And Gas ◽  
Offshore Oil

The Bass Strait of Australia is the location of significant offshore oil and gas production. At the time of this writing eight self-contained drilling and production platforms as well as many miles of submerged pipeline comprise the Esso Australia Ltd. (EAL) and Broken Hill Proprietary Company Ltd. (BHP) operation in the Bass Strait. During the course of the next five years significant additional development and platform construction will take place in this offshore oil and gas area. Observation of offshore wind and wave conditions are greatly facilitated by the presence of fixed platforms from which to collect data. Visual observations of waves along with measurements of wind speed and direction and barometric pressure from Bass Strait Platforms have been routinely recorded and reported to the Australian Bureau of meteorology for more than ten years. Close cooperation between EAL and the Meteorological Bureau has resulted in continuous weather forecasts for the Bass Strait region. In March of 1977 EAL decided to upgrade the instrumentation on two of the platforms in the Bass Strait. The purpose of this was to reduce the subjectivity of visual wave observations and to eliminate the uncertainty of such observations at night and during inclement weather. Additionally it was felt that by instrumenting both a deep water (250 feet) and a shallow water (150 feet) platform the data collected would help quantify the observation that the storm waves seemed to be larger in deeper water than in shallow water. It was felt that use of the data along with a computer based wave hindcast model would aid in the development of an understanding of the Bass Strait wave environment. Two platforms were chosen for instrumentation. The Barracouta (BTA) platform in 150 feet of water, located about 20 miles from shore, was instrumented with a wavestaff. The Kingfish B (KFB) platform in 250 feet of water, located about 50 miles southeast of BTA, was instrumented with a wave staff, electromagnetic current meters, anemometer, barometer and air temperature sensor. Figure 1 shows the location of these platforms in the Bass Strait. The design, fabrication and installation of the data station was performed by Evans-Hamilton Inc. of Houston, Texas.

Drilling and Service Contracts in Offshore Oil and Gas Operations

1973 ◽  
Vol 11 (3) ◽  
pp. 480
Author(s):  
J. M. Killey
Keyword(s):  
Oil And Gas ◽  
Oil Industry ◽  
Offshore Drilling ◽  
Oil Companies ◽  
Drilling Rig ◽  
Service Contracts ◽  
Oil And Gas Operations ◽  
Offshore Oil And Gas ◽  
Offshore Oil ◽  
Offshore Operations

As onshore oil and gas deposits are becoming more difficult to locate, and as the world demands for energy continue to increase at an alarming rate, oil companies are channeling much of their exploration activities towards offshore operations, and in particular, towards operations centered off Canada's coast lines. Because of the environment, offshore drilling presents problems which are novel to the onshore-geared oil industry. J. M. Killey discusses in detail many of the considerations involved in drafting the offshore drilling contract, concentrating on problems such as the liability of the various parties; costs; scheduling; pollution; conflict of laws; etc. Similarly, he discusses service contracts (such as supply boat charters; towing services; helicopter services; etc.^ which are necessity to the operation of an offshore drilling rig. To complement his paper, the author has included number of appendices which list the various considerations lawyer must keep in mind when drafting contracts for offshore operations.

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